Moderated by Dipl.-Ing. Merkur Alimusaj (Head of Technical Orthopaedics, Department for Orthopaedics, Trauma Surgery and Paraplegia – University Clinic Heidelberg – Germany) the symposium explored the role of real-world evidence in advancing prosthetic integration, with expert presentations from Kat Sizer (physiotherapist, Dorset Orthopaedic, Ottobock.Care – UK), Tim Baumeister (CPO, Head of Prosthetics lower extremities DACH, Pohlig GmbH – Traunstein, Germany), Thomas Maximilian Köhler MSc (CPO Research Engineer, Clinical Research & Services, Ottobock SE & Co. KGaA – Göttingen, Germany), and Dr. Ernesto G. Trejo (Clinical Project Manager, Clinical Research & Services, Ottobock Healthcare Products GmbH – Vienna, Austria).

This online symposium highlighted the impact of the new microprocessor-controlled knee (MPK) prosthesis Genium X4 on biomechanics, mobility, and patient outcomes, as well as the latest advancements in socket technology, tailored physiotherapy training, and the unique challenges of integrating microprocessor-controlled knees into both socket and osseointegration systems. The event provided a platform for leading professionals to exchange insights, foster innovation, and enhance the future of prosthetic care.

Key patient benefits of Genium X4

Ernesto Trejo provided an overview of studies conducted during the development phase of the Genium X4 knee joint. He highlighted that these studies are not only crucial for verifying compliance with safety and performance standards but also for showing that participants experience measurable benefits from the new technology. Furthermore he presented the results of the last clinical trial in Germany.

In this case, it was a pilot with 8 participants that represented the Genium X4 target population. The outcomes used to assess participant’s experience with the new MPK focused on safety (stumbles and falls), prosthetic usage, specific situations where new functions were applied, the impact of new functions in activities of daily living, mobility, preference, and satisfaction.

“It is challenging to see improvements in some of these outcomes, as Genium and X3 are already the safest MPKs on the market”, Trejo said. Despite this, the study reported decreases in stumbles and falls, alongside positive feedback (better than Genium/X3) on factors such as exertion, required concentration, comfort, and the usefulness of the new features.

In conclusion, all participants preferred the Genium X4 over X3 at the end of the 16 week-trial with the final prototype. “Participants referred to Genium X4 as lighter, more intuitive, more natural.” Given the subjective nature of this feedback, biomechanical measurements during the study were critical in providing objective results that could be linked to participants' experiences.”

Biomechanical study results confirm improvements in daily activities with Genium X4

Drawing on biomechanical study results and patient-reported outcomes Thomas Maximilian Köhler presented key features of the prosthetic knee joint and explained how new functions enhanced patient benefit. “Genium X4 provides adjustment settings for fine-tuning of the stance and swing phase control to fit the needs of the user more individually. Furthermore, three entirely new functions were implemented”, Köhler said.

1. Walking initiation of the prosthetic side typically occurs with an extended knee joint, because criteria for switching into swing phase are not fulfilled (when using an MPK with default stance principle). The new function “start-to-walk” enables knee flexion with a partially unloaded prosthesis. Users reported this as very beneficial in crowded spaces or “stop-and-go” situations.

2. The new function “optimized backwards walking” enables knee flexion limitation between 15-30° when walking backwards. This avoids excessive knee flexion and provides an enhanced acceleration phase. Users reported that this improves balance and is helpful for pulling heavy objects.

3. When walking up ramps, state-of-the-art MPKs do not adapt knee flexion angle at initial contact. The new function “optimized slope ascent” however make it possible to different inclinations. Users reported walking uphill feels easier and more natural.

The study included 8 participants (6 unilateral, 2 bilateral). For the biomechanical analysis, the Genium X4 was compared with the Genium X3. Patient-reported outcomes were mapped with the biomechanical results. Walking initiation showed a more natural movement pattern of the prosthetic side and reduced compensatory strategies of the pelvis and upper body. When walking backwards, anterior-posterior ground reaction force was higher during prosthetic side push off, indicating an improved acceleration phase. Walking up ramps was performed with a more natural movement pattern of the prosthetic leg. Furthermore, contralateral ankle power and range of motion of plantar flexion showed reductions, indicating reduced compensatory movement. “Clinically relevant improvements in daily activities are possible with the new functions in Genium X4. MPKs have been in development for more than three decades. However, improvements can still be achieved, particularly by refining the control algorithm”, Köhler explained.

Innovative prosthetic socket designs

Tim Baumeister reported on the design variants of prosthetic sockets when using MPKs: “The main focus when providing prosthetic care for amputees is on the connection between the industrially manufactured fitting, structural and functional parts and the amputation stump. The prosthetic socket is attributed particular importance in prosthetic care. It is the most important component.” Baumeister emphasized that the demands on the socket are wide-ranging. The socket must transfer all the forces acting in the axial and horizontal direction, accommodate the residual limb volume, enable the prosthesis to be controlled and realize the static structure depending on the individual malposition.

In his presentation, Baumeister also presented the importance of adaptive properties in prosthesis sockets. He showed fitting examples from knee disarticulation, transfemoral and hip prosthetics. The combination of flexo-elastic HTV and RTV silicones with rigid and stable carbon materials makes it possible to implement large, flexible and elastic areas on the prosthesis socket systems. This has a positive effect on activities of daily living, such as sitting, eating and walking. As a result, the acceptance of the prosthetic fitting increases and targeted rehabilitation of the affected users is made possible.

In order to optimize the quality of socket fittings, ottobock.care Pohlig collects biometric data from the stumps as part of the ‘PBSS project’ (Pohlig Bionic Socket System) and enters it in databases. Baumeister sees the development of statistical models to generate information for socket modelling as a great opportunity offered by digitization. In the future, that could meet the requirements for individualized, high-quality prosthesis care.

Empowering therapists: tools and strategies for microprocessor knee training

In her presentation, Kat Sizer shared various tools and resources available for therapists to aid patients in learning the features of their MPKs. Based in the UK, she highlighted relevant guidelines and policies that assist therapists in effectively trialing these advanced devices with their patients. With a decade of experience in the private sector, Sizer has worked closely with numerous patients transitioning to microprocessor technology, particularly focusing on the Genium and Genium X3 models.

She discussed strategies employed to support the learning process, emphasizing the importance of utilizing a variety of teaching methods to help patients understand the features of their knees. She stressed the necessity of ensuring that each feature is used effectively and confidently across different environments. Additionally, Sizer addressed the time required for patients to adapt to a new knee, noting that various factors can complicate the timeline for this adjustment.

In addition, Sizer shared comments of her patients who have had an osseointegrated implant, discussing the considerations that osseointegration can bring to microprocessor use. The session concluded with comments from the patients about their positive experience of using Genium X4.

Wrap-up

The recent event provided a comprehensive overview of the advancements and clinical insights related to the microprocessor knee joint Genium X4. Concluding the symposium, Merkur Alimusaj highlighted the vital role of clinical trials in establishing safety and performance standards while also measuring participant benefits. Three new functions were introduced: „Start-to-Walk“ which facilitates easier movement in crowded situations, “Optimized Backwards Walking” designed to improve balance, and “Optimized Slope Ascent” which enhances movement when navigating ramps.

Additionally, the significance of the prosthetic socket and its role as the interface between limb and device was emphasized. The use of flexible materials increases comfort, while adaptive designs boost user satisfaction. Initiatives like the PBSS project harness biometric data for personalized solutions, and digitization promises tailored fittings that enhance amputees' quality of life. The symposium also highlighted the importance of patient education, presenting resources and tools for therapists to effectively guide patients in utilizing their MPKs. The value of diverse teaching methods was stressed to help patients build confidence in using their technology across different environments. User feedback, especially from those with osseo-integrated implants, indicated positive experiences and adaptability.

Overall, the event emphasized the significant advancements in microprocessor knee technology with Genium X4, showcasing not only improvements in safety and performance but also the profound impact on users’ daily lives.

To view the recording of the symposium, please register using this link:Real-World Evidence and Innovations in Prosthetic Integration (ottobock.com)
After successful registration, you will receive the link to the recording in the confirmation e-mail.